St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common or Floratam-like variety (highly visible stolons and coarse blades)
Hardiness Zones
USDA Hardiness Zones 8-11; poor cold tolerance; goes dormant and turns brown when soil temperatures drop below 55°F.
About This Grass
A coarse-textured, low-growing grass with a vibrant blue-green to dark green color. It is characterized by thick, fleshy stolons and flowering culms (as seen in the image) featuring spike-like racemes where seeds are embedded in a corky rachis.
Blade Characteristics
Coarse blades (8-10mm width), flat to folded, rounded/obtuse tips. Vernation is folded in the bud. Ligule is a fringe of short hairs; auricles are absent. Leaves are oppositely arranged on stolons.
Root System
Fibrous and relatively shallow to moderately deep; relies on thick stolons for lateral spread. Forms heavy thatch; establishment is moderate to slow via sod or plugs.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and Mediterranean; well-adapted to tropical and subtropical climates
Growth Habit
Stoloniferous (spreads via thick, creeping above-ground runners); forms a dense, carpet-like mat
Sunlight & Water Needs
Partial sun to full sun (4-6 hours minimum); high shade tolerance compared to other warm-season grasses. High water needs; poor drought tolerance compared to Bermuda or Zoysia.
Mowing & Maintenance
Ideal height 2.5 to 4.0 inches; frequency weekly during growing season; 2-4 lbs N per 1000 sq ft annually; high maintenance level due to water and pest needs.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance; poor wear tolerance (delicate blades crush easily); susceptible to Chinch Bugs and Gray Leaf Spot.
Ecological Information
Introduced/Naturalized in many coastal areas; provides soil stabilization in sandy coastal soils; low wildlife value; not typically invasive in non-tropical climates.